907.3 Vent Stacks and Relief Vents.
San Francisco Building Inspection Commission Codes · 2022 edition · ingested 2026-07-08 · San Francisco
907.3 Vent Stacks and Relief Vents. Every building in which plumbing is installed shall have at least one main stack which shall run undiminished in size and as directly as possible from each building drain serving said building through to the open air above the roof.
For the purposes of this section, the main stack shall be defined as the largest size stack that is connected to a building drain or sewer.
A vent stack shall be installed with a soil or waste stack whenever relief vents or other branch vents are required in two or more branch intervals. A vent stack shall be installed in accordance with Section 706.1.
T he size of the soil stack shall be determined by the total fixture units on that stack as per Table 703.2.